Device for extracting cores from wells.



BEDU'S D. DODDS, 0F HUMBLE, TEXAS.

DEVICE FOR EXTBACTING' COBES FROM WELLS.

Specification of Letters Patent.

Application filed April 2, 1917. Serial No. 159,248.

To all whom it may concern:

Be it known that I, REoUs D. Doons, a citizen of the United States, residmg at Humble, in the county of Harris and State of Texas, have invented certain new and useful Improvements in Devices for Extracting Cores .from Wells, of which the following is a specification.

This invention relates to new and useful improvements in a device for extracting cores from wells.

In drilling wells, particularly oil wells, it is often desirable to obtain samples of the formation through which the drilling tool is passing for the purpose of determining the presence or absence of oil or other minerals. The object of this invention is to provide a device of the character described to be used for obtaining samples of the core formed by the drilling tool at any depth, and withdrawing the same to the surface during the process of. drilling.

. device into the well, and

With the above and other objects in view, the invention has particular relation to certain novelfeatures of construction, arrangement of parts and use, an example of which is given in this specification and illustrated in the accompanying drawings, wherein:

Figure 1 is a vertical sectional view of a drill stem showing the device in operative position therein.

Fig. 2 is a transverse sectional view of the device taken on the line 2--2 of Fig. 1.

Fig. 3 shows a vertical sectional view of an implement employed for lowering the Fig. 4 is a vertical sectionalview of a fishing tool for withdrawing the device from the well.

Referring now more particularly to the drawings wherein like numerals of reference designate similar parts in each of the figures, the numeral 1 refers to a tubular drill stem having the shoe- 2 secured upon the lower end thereof, provided with water passageways 3, 3, on each side. The shoe also has a vertical bore 4 therethrough for a purpose to be hereinafter stated.

.The numeral 5 refers to a tubular barrel whose upper end is reduced and carries the conical. shaped head 6 having the annular groove 7 therearound. Within the barrel is the valve seat 8 controlled by the valve 9 which permits the fluid to 'pass upwardly through the barrel and the said fluid may pass thence out into the drill stem through the orifices 10, 10. When in position, this barrel rests upon the shoe and its lower end is flared so as to entirely surround thebore 4. Above the valve 9 the barrel has an oblong slot 11 through which the dog 12 projects. This dog is hinged to the inner side of the barrelat the point 13 and a fiat spring 14 is secured at one end to the barrel and its other end rests against the dog to project it through the slot 11. The inner side of the drill stem carries a fixed shoulder 15 provided to engage against the end of the dog 12 so as to force the barrel 5 to rotate with the drill stem 1. When the barrel is in position resting upon the shoe 2, it is held firmly in position by means of the flexible fingers 16, 16, whose upper ends are secured to the drill stem and whose'lower ends engage against the, upper side of the annular shoulder 17 of the barrel 5. Two spring dogs 18, 18, areprovided which are fixed at one end. to the outer'side of the barrel 5 and whose other ends are turned inwardly and formed into cutting'edges in alinement with the slots 19, 19, cut through the barrel near its lower end.

The lower end of the shoe is serrated forming sharp cutting teeth as 20 and as said shoe progresses down-through the formation, a core is formed which passes through the bore 4 up into the barreL.

For the purpose of lettingthe device down into position, I have provided the implement shown in Fig. 3, wherein the numeral 21 refers to a tube having a spider 22 fixed therein near its lower end, with a central orifice 23 through which the rod 24 passes,

'said rod having an enlarged head 25 at its upper end to prevent its detachment froni the spider. The lower end of the rod carries a frame 26 to opposite sides of which are pivoted the levers 27, 27 the lower ends of said levers being turned inwardly forming the fingers 28 28, provided to engage in the groove 7 of the head 6. The upper ends of "these levers are arcuate inform, being Patented Jan. 8,1918.

curved outwardly and interposed between them is the push spring 29 provided to hold.

the fingers 28 in engagement in said groovel 'In order to lower'the device into'the well, the fingers 28 are engaged over said head as shown in Fig. 3 and-the entire device then lowered through the medium of the tube 21,

the head 25 engaging against the spider 22. When the barrel 5 seats upon the shoe 2 and the fingers 16 have engaged over the shoulder i 17, the tubing 21 'is forced farther downwardly and will pass over'the upper ends ofthelevers 27 and force them together disengaging thefingers 28 from the head 6 and the catches 30 carried by the outer sides of the upper ends of said levers 27 engage in corresponding recesses 31, 31, in the inner side of the lower end of the tube 21 and the implement may then be lifted out of the well leaving the device in position for operation in the drill stem.

In Fig. 4 I have shown a form of fishing tool for withdrawing the device from the drill stem. This tool consists of a casing 32 whose upper end) is reduced, formin a bearing 33 and provided with fluid out ets 34. A stem 35 operates through said bearing to the upper end of which the cable 36 is attached. To the lower end of this stem is secured a hood 37 of a size and form to fit over the head 6, said hood being provided with a bushing 38 forming a close fit with the casing 32. When a core has been formed and it is desired to withdraw a portionthereof, the fishing tool is let down into the drill stem by means of the cable 36 until it rests upon the shoe 2. This casing fits closely over the barrel 5 and as it passes down it disengages the fingers 16, 16 and the dog 12, whose upper side is beveled and when its lower end comes into contact with the dogs 18, it will force them inwardly through the slots 19 and they will cut into "and sever a portion of the core. When the casing 32 is seated on the shoe,'the fingers 39, 39, carried by the inner side of the hood 37 will engage under the head 6 as shown in Fig. An upward pull upon the cable 36 will draw the barrel 5 upwardly until the head 6 engages against the reduced upper end of the casing and the entire device and fishing tool maythen be withdrawn from cable 36.

What I claim is: v 1. The combination with a drill stem havthe well, through the instrumentality of the ing a core forming boring tool secured to v the lower end thereof and provided with a bore to receive said core, of a tubular barrel secured in said stem, and when in operative position, resting upon said tool and whose lower end is provided with slots, interengaging means carried by the stem and barrel respectively whereby the barrel is forced to rotate with the stem, and means working through said slots provided to engage with and sever the core in the barrel.

2. The combination with a drill stem havthe lower end thereof which is provided with a bore to receive the core, of a tubular barrel, having a side slot, secured in said stem and when in operative position resting .upon said tool and whose lower end is provided with apertures, a fixed shoulder'ca'rried by the stem, a dog hinged within the barrel and projecting through said slot, a flexible spring normally holding said dog projected through the slot to engage with 'said shoulder and force the barrel to rotate position resting upon said tool an whose lower end is provided with slots, interengaging means carried by the stem and barrel.

respectively whereby the barrel is forced to rotate with the stem, means arranged to project through said slots and provided to engage with and sever the core in the baring a core forming boring'tool secured to a rel, a casing provided to fit over said barrel 1 and when in position overvthe barrel, to disengage said interengaging ,means andto force the core severing means through said slots and into engagement with the core and a cable attached to said casing.

4. The combination with a drill stemhaving a core forming boring tool secured to thelower end thereof and provided with a v bore to receive said core, of a tubularbarrel secured insaid stem and when in operative positlon resting upon said tool and whose lower end is provided with slots, means working through said slots provided to en-v v.

gage with and sever the corein thebarrel, a casing provided to fit over the barreland to' force said means through the slots into engagement with the core, a means for engaging said barrel to said casing, and a cable attached to the casing for withdrawing said casing and barrel.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

REDUS D. DODDS;

Witnesses:

A. C. Srnmorinnn, E. V. HARDWAY, 

